Vitamin D Deficiency in Mexican Pregnant Women: Is Supplementation with ≤400 IU/day Enough?

Abstract

Controversy remains surrounding vitamin D routine supplementation in healthy pregnancy, and the doses are unclear. The aim of this study was to describe maternal vitamin D status throughout pregnancy in a group of Mexican women and evaluate the effect of frequently prescribed doses of vitamin D3 on longitudinal 25-OH-D concentrations, adjusting for obesity, season, and other factors. We conducted a cohort study (Instituto Nacional de Perinatología-INPer) (2017–2020)) of healthy pregnant women without complications. Pregestational overweight/obesity (body mass index ≥ 25), vitamin D3 supplementation (prescribed by physician; 0–250, 250–400, and >400 IU/day), and serum 25-OH-D concentrations (ELISA) were evaluated in each trimester of pregnancy. Vitamin D deficiency or insufficiency was computed (<20 and <30 ng/mL, respectively). We studied 141 adult women; 58.5% had pregestational obesity or overweight. In the first trimester, 45.8% of the women were supplemented with vitamin D3; 51.4% had vitamin D insufficiency and 37.3%, deficiency. In the third trimester, 75.4% of the women were supplemented, and 20% of them still had deficiency. The final general mixed linear model showed that 25-OH-D significantly increased throughout pregnancy (p < 0.001); the highest increase was observed in the third trimester in women with doses >400 IU/day of vitamin D3 (+4 ng/mL, 95% CI: 1.72–8.11 ng/mL). In winter/autumn, 25-OH-D concentrations were also lower (p ≤ 0.05). In this group of pregnant Mexican women, the prevalence of vitamin D deficiency and insufficiency was high. A higher increase in 25-OH-D concentrations during pregnancy was observed when the women were supplemented with >400 IU/day. Common supplementation doses of 250–400 IU/day were insufficient for achieving an adequate maternal vitamin D status.

Vitamin D Status and Its Determinants in Mexican Pregnant Women from a Rural and an Urban Area: A Comparative Study

“…It has been widely reported that these two seasons can reduce vitamin D concentrations due to an association with sunlight scarcity in some countries [ 28 , 29 , 30 ]. Finally, in a previous report of the OBESO cohort, in Mexican women, the 25(OH)D concentrations decreased by −1.85 ng/mL (95% CI: −2.99 to −0.72 ng/mL) in women during autumn/winter, compared to the spring/summer season [ 15 ].…”

“…Height and weight were measured using a steady digital stadiometer (model 264, SECA, Hamburg, Germany) and bioimpedance equipment (model 230, Inbody, Seoul, Korea), respectively, in order to calculate the pregestational body mass index (pBMI). Women were classified as normal weight (pBMI > 18.5 < 24.9), overweight (pBMI ≥ 25), or obese (pBMI ≥ 30), according to the WHO parameters [ 15 ]. Demographic information (education, occupation, and socioeconomic status) and clinical data (parity) were obtained.…”

“…In Mexico, a cross-sectional study in mother-child binomials showed a prevalence of VD-D in 61% of pregnant women during the third trimester and in 98% of babies [ 14 ]. A recent report from a cohort of Mexican healthy pregnant women showed that only 39% of them had adequate 25(OH)D concentrations during the third trimester of gestation, and 20% had a deficient status [ 15 ].…”

Ultra-Processed Food Consumption during Pregnancy and Its Association with Maternal Oxidative Stress Markers

“…This is a secondary analysis from the OBESO (Origen Bioquímico y Epigenético del Sobrepeso y la Obesidad) perinatal cohort (2017–2020), which aimed to define the different determinants of obesity programming and was conducted at the Instituto Nacional de Perinatología Isidro Espinosa de los Reyes, in Mexico City, Mexico. The cohort characteristics have been described previously [ 31 ]. Women who agreed to participate signed an informed consent.…”

Association between 25-OH Vitamin D Deficiency and COVID-19 Severity in Pregnant Women

“…Furthermore, maternal vitamin D deficiency represents a public health issue and is considered the least diagnosed and treated nutrition deficiency worldwide [ 48 , 49 ]. In a recent cohort study, we showed that the prevalence of vitamin D deficiency (<20 ng/mL) and insufficiency (20 ng/mL–30 ng/mL) was high in Mexican pregnant women [ 50 ].…”